Diamagnetic field states in cosmological plasmas

Abstract

Using a generally covariant Electro-Vortic (magnetofluid) formalism for relativistic plasmas, the dynamical evolution of a generalized vorticity (a combination of the magnetic and kinematic parts) is studied in a cosmological context. We derive macroscopic vorticity and magnetic field structures that can emerge in spatial equilibrium configurations of the relativistic plasma. These fields, however, evolve in time. These magnetic and velocity fields fields are self-consistently sustained in a diamagnetic state in the expanding Universe, and do not require an external seed for their existence. In particular, we explore a special class of magnetic/velocity field structures supported by a plasma in which the generalized vorticity vanishes. We derive a highly interesting characteristic of such "superconductor-like" fields in a cosmological plasmas in the radiation-era in early Universe. In that case, the fields grow proportional to the scale factor, establishing a deep connection between the expanding universe and the primordial magnetic fields.

On the quadruple Beltrami fields in thermally relativistic electron-positron-ion plasma

“…More recently, Asenjo and Mahajan studied similar perfect diamagnetic states in a cosmic plasma consisting of electrons and positrons in the radiation epoch of the early universe. They proposed that for the expanding cosmological plasmas in a curved space-time, the electromagnetic, kinematic, and thermal forces can come to balance, resulting in the disappearance of the generalized helicities of plasma species, and as a result, there is a diamagnetic trend in the magnetic field [51].…”

“…The investigation of these QB states has shed light on the role that degeneracy-induced relativistic temperature has on the formation of multiscale structures [47,48]. Plasma relaxation is also the focus of a great deal of research that takes into consideration the implications of general relativity as such relativistic plasmas are also encountered in the vicinity of black holes [49][50][51][52].…”

Relaxation of relativistic pair plasma in a massive photon field

“…Some applications of Beltrami states in astrophysical phenomena are solar flares (Ohsaki et al 2002;Kagan & Mahajan 2010), solar arcades and loops (Bhattacharyya et al 2007;Fuentes-Fernández, Parnell & Hood 2010), coronal heating (Mahajan et al 2001;Browning & Van der Linden 2003), large-scale dynamo and reverse dynamo mechanisms (Mininni, Gómez & Mahajan 2002;Mahajan et al 2005;Kotorashvili, Revazashvili & Shatashvili 2020;Kotorashvili & Shatashvili 2022), turbulence (Krishan 2004;Krishan & Mahajan 2004) and striped wind of pulsar nebula (Pino, Li & Mahajan 2010). Furthermore, the application of Beltrami states has also been expanded to encompass curved space-time, allowing for their utilization in the modelling of plasmas located in the vicinity of black holes as well as the early universe (Bhattacharjee et al 2015;Bhattacharjee, Feng & Stark 2018;Asenjo & Mahajan 2019;Bhattacharjee 2020;Bhattacharjee & Feng 2020).…”

“…Furthermore, the application of Beltrami states has also been expanded to encompass curved space–time, allowing for their utilization in the modelling of plasmas located in the vicinity of black holes as well as the early universe (Bhattacharjee et al. 2015; Bhattacharjee, Feng & Stark 2018; Asenjo & Mahajan 2019; Bhattacharjee 2020; Bhattacharjee & Feng 2020).…”

Self-organized multiscale structures in thermally relativistic electron-positron-ion plasmas

“…The salient features of DB states are the strong coupling of the magnetic field and flow, high beta, diamagnetism and self-confinement of plasmas [7][8][9]. The DB states have been extensively used to model fusion [10][11][12][13] and astrophysical plasmas such as flow generation in solar atmosphere and compact astrophysical objects [14,15], dynamo and reverse dynamo mechanisms [16], multi-scale structure formation in space and astrophysical plasmas [17], formation of solar arcades and coronal mass ejection [18,19], and diamagnetic states in cosmological plasmas [20]. The inertia of the plasma species also plays a very important role in the process of self-organiztion and introduces coupling of multiple Beltrami states.…”